[link|http://www.cube-zero.net/NeXT/?main=history|http://www.cube-zero...eXT/?main=history]
To this end, NeXT released NEXTSTEP for Intel, Sparc, and HP which allowed the software to run on Intel 486 and Pentium processors, as well as Sun SPARC-based computers and Hewlett-Packard HP-UX workstations. NeXT continued to produce the NEXTSTEP operating system until release version 3.3 and created the OpenStep API specification for operating systems in conjunction with Sun Microsystems.

thanx,
bill